lemon-mirror:
Home >> Toyota >> 1991 >> MR2 2.0 S >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - System/Component Tests >> Idle Control Systems >> Idle Speed Control (ISC) System >> 2.2L

Idle Speed Control (ISC) System: 2.2L

  1. Warm engine to normal operating temperature. Ensure idle speed is correct. Apply parking brake, block drive wheels and place transaxle in Neutral.
  2. Install jumper wire between terminals TE1 (or T) and E1 of check connector located near left shock tower. See Fig 1. Engine RPM should increase to 1000-1300 RPM for 5 seconds and then return to idle.
  3. If engine RPM was not within specification, check ISC valve, wiring to ECU, and ECU grounds. If engine RPM was within specification, remove jumper wire. Turn ignition off.
  4. Unplug ISC valve connector on bottom of throttle body. Using ohmmeter, measure resistance between terminals B+ and ISC1, and between ISC2 and B+. See Fig 2. Replace valve if resistance is not within 19.3-22.3 ohms.
Fig 1: Connecting Jumper Wire in Check Connector
G118943Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 2: Checking ISC Valve (Celica Shown; MR2 Similar)
G118944Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002